Kuroneko's Koneko
by MoonlightBushido
Summary: How would things change with Train Heartnet being Nana's younger maternal half brother? This is also a crossover with D N Angel. Fem Tsuna and Daisuke/Dark pairing.
1. Chapter 1

Prologue

Train Heartnet, the former Chronos number XIII Kuroneko, honestly hadn't known he had an older sister that had been given up for adoption because his mother had been too young to take care of her, and that she had been raped by her best friend's father. It had been Sven to discover this tidbit of information, and inform him of Sawada Nana, wife to Iemitsu, the Young Lion of the Vongola, and their External Advisor. To all indications Nana had no clue what her husband's real job was. By the time he made it to the Sawada home in Namimori his older half-sister was dead, and his niece would have been next if he hadn't slipped straight into Kuroneko mode. Hades made short work of the Idiots that had gone after his only remaining family. He does find out the Idiots do have bounties, which means the Sweeper was still going to get paid for dealing with such Trash.

With help from the Sweepers he proves that he is in fact Nana's younger half-brother, and gains custody of his niece when his brother-in-law can't be bothered to answer the damn phone, or any missives sent to him either. If the Vongola weren't going to protect little Shizu then _he would_. First he would need to set up some place permanent as a home, Shizu would need stability, therapy, and time. She could be homeschooled for a little while. He finds a decent home in Azumano, and settles in with Sven, Eve, and Shizu. The Sweepers provide the psychologist for Shizu, one that specialized in children traumatized by things like seeing their parents murdered in front of them.

Train would never regret his decision to settle in Azumano, or buy the house next door to the Niwa Family. As Daiki noticed a very troubling seal on Shizu, one he and his daughter researched extensively on how to remove. The Vongola were going to be in for one helluva surprise, as Shizu would be trained as an assassin/sweeper by Train, and Phantom Thief by the Niwas.

Seven Years Later:

Shizu grins outright at the horrified exclamation from Daisuke on his fourteenth birthday. Emiko had filled her in, since she suspected that Shizu would be the trigger for Daisuke and Dark. It was unusual, but it had happened before. Shizu's birthday had been a little less than a month before, and she takes in the taller form with violet hair and eyes. She gets her paintball sniper rifle ready, and slips out before her friend can. Well, she had accepted Daisuke's confession, but she also wanted to meet Dark. It was Dark himself that came to retrieve her after she allowed him to escape so easily, " It's not often my Tamer and I have the same trigger. "

" Emiko suspected that might happen. Now, can we get out of here. Uncle Train doesn't mind if I help you out. Hell, he started out as an assassin, then he became a Sweeper/Bounty Hunter. " Shizu deadpans.

Dark cackles merrily at this, because honestly, Shizu was perfect for Daisuke. Though even he had been pissed that such a piss poor seal had been put on a Sky Flame of that purity, _that was active_. Thankfully Daiki and Emiko did find a way to keep people from noticing she had been unsealed, and to keep Sky Attraction from being a problem as well.

Chapter 1

Daisuke yawns when he wakes up for the day, not even reacting to Shizu's presence beside him. Sven, Eve, and Train had gone to help out an old friend of theirs, Rinslet, leaving Shizu with his family. Growing up with Train's influence meant this Daisuke Niwa was not nearly as shy. He'd still blush when seeing Shizu in a bikini, and in their shared mindscape even Dark reacted to that stimuli. Yes, Dark was an unrepentant flirt, but Shizu was the first female since Harada Rika that he'd felt anything for. The mere fact Shizu didn't mind them sharing her, they were the same technical person, well, it was her that had kept him from being sealed back into the Black Wings because she had Harmonized with him as her Cloud, and Daisuke as her Rain.

Train had been the one to teach Daisuke how to shoot, as he put it, just because he knew how to use a gun didn't mean he had to use it. Daisuke had learned how to wield a sakabato as his weapon. He was in fact descended from Himura Kenshin, he whom had been known as Hitokiri Battōsai in the Bakumatsu. Honestly he had no problems with Train having been a former assassin turned Sweeper. It had been a shock to realize the Hiten Mitsurugi-Ryū was still being taught. Emiko had no problems with signing her son up for lessons, and like Kenshin his light frame allowed him to utilize the style to its fullest, including the double Battōjutsu using the sword and the sheath. Daisuke did have a katana as well, that could handle his Flames, just in case the Vongola decided they wanted Shizu back.

Anyone that even _attempted_ to take Shizu from him would be met with lethal force. Dark was in agreement with that, as the Mafia was full of hardened killers. The Vongola hadn't protected Shizu and her mother when it counted. Train had left no forwarding address behind, and the Sweepers had made damned certain no names were mentioned either. This meant that the Vongola honestly had no idea what had happened to their External Advisor's Family, and Train, with help from the Niwa Family, had left plenty of false trails. If they wanted his niece they would have to earn her. He was sincerely hoping she would have all of her Guardians before she was found. Hell, Eve was her Lightning Guardian, and the genetically engineered bioweapon had actually cackled when she woke up her Flames, and turned them Useful. Train had honestly been terrified in that moment. Eve was already a beast to put down, add Lightning Flames into that as well...Verde loved the girl, though not even the Lightning Arcobaleno was stupid enough to mess with someone closely associated with Kuroneko.

Verde had taught her how to use her Flames, and upgraded her nanites as well. Daisuke remains still as Shizu snuggles in closer to him. Nightmares had plagued her sleep, not enough to wake her, but enough that his mother forewent her usual wake up method for them. That and Shizu was nasty when woken up before she wanted to be. Much like Train she was a lazy cat, and she did not like her sleep interrupted for Stupid reasons. The one and only time Emiko woke her up in her usual way on a weekend where she could sleep in...Shizu responded in kind, and took control of the traps in the Niwa home. Dark had been howling in their shared mindscape at the fact Shizu made Emiko go through the damned traps. Hell, she trapped Emiko's room, and only Emiko was affected as well. Kosuke couldn't find it in himself to pity his wife, she brought it on herself by messing with the Kuroneko's Kitten.

Shizu was very much like her uncle, an uncle that was there for her, protected her, taught her how to defend herself. She did love the lessons on being a phantom thief, hell, Dark loved the fact that she had no qualms about helping him either. Daisuke, originally had not liked the family business, but then Train had revealed Shizu's heritage. That woke up the sleeping warrior that had been hiding inside of Daisuke. He had inherited his red hair from Himura Kenshin after all.

Namimori:

Reborn, the World's Greatest Hitman frowns heavily when he reaches the Sawada home, and finds the old bloodstains. He breaks into the police station, and curses Iemitsu's incompetence. His wife had been murdered, apparently had been given up for adoption, and her younger half-brother had been granted custody of Shizu. It had only been the brother's intervention that saved Shizu as well. Apparently he happened to be a Sweeper. Had Reborn known Nana's half-brother was in fact the retired Kuroneko...he'd really be swearing. Kuroneko was one assassin/eraser no one wanted to deal with. Being good enough to earn a number in the Chronos Numbers, there was a reason why the Vindice did not mess with Chronos, or retired numbers either. They always went after the absolute worst scum of the Earth.

The Hitman turned Home Tutor calls Timoteo to fill him in on what he had learned. It would take six months to track Shizu down, because her name had been legally changed, and she wore contacts that changed her eye color to gold, she had needed to reinvent herself, and her therapist actually agreed with the idea. The further she distanced herself from the girl she had been the better. Of course, Train had no problems with training his niece in acrobatics, and more to the point had actually signed her up for gymnastics lessons as well. Like him she was very agile, could shoot gun from any angle, and mastered more than one type of firearm as well.

Azumano:

The fifteen year olds make their way into the kitchen safely, though Shizu's dart gun received a lot of use on the damned inflatable, and infantile traps Emiko favored. Emiko would have said something, but Shizu now had her paintball gun pointed at her, a dark look in her eyes. Daisuke smirks while Dark cackles in the mindscape. Shizu fit perfectly with a family of phantom thieves, though Daisuke had worked his ass off to learn several languages. He and Dark were in agreement that the Vongola Half Rings needed to be grabbed up before some got Stupid. Hence why he had no problems with being a phantom thief. Stealing from the Vongola, oh, that would really get Dark's name out there. Even better, was the fact they planned to make a proper spree of it while his mother and Shizu enjoyed a month long spa visit.

No way in Hell was Daisuke allowing his girlfriend to go anywhere near Italy. The teens eat their breakfast, and then dress for a day in the black markets. Dark took over for this, mostly because _he had reason to be there_ while Daisuke didn't...yet. Shizu went there all the time with Train, mostly to hopefully find her Guardians, as she did not want them to be civilians. That, and if she found them all before the pain in the ass known as Reborn showed up all the better. Then again, none of them knew she already had her Storm in Rinslet Walker, her Flames would switch from Latent to Active very shortly. Shizu was even receiving training from a female oyabun on how to run a Organized Crime group, once Shizu explained her heritage, the woman agreed to an Alliance should she be tapped for Decima.

Of course no one would ever suspect the Decima candidate to be a harmless school girl on her school's gymnastics team. Shizu deliberately made herself look meek in school, though everyone knew damned well her inner bitch was not to be fucked with. No one wanted her inner bitch to come out again. Though even Dark had enjoyed Mafia Land, and they had played himself off as a Dark Mousy fanboy, one that cosplayed as his favorite thief. Colonello had been so put out that Dark, Shizu, and Train had all gotten through his obstacle course like it was mere child's play. Then they critiqued the poor sods that went after them. Daisuke had been laughing his ass off in his mindscape. Kuroneko was still a well known name, and had an open invitation to Mafia Land. They were just considered his apprentices.

Dark would never sully his reputation with murder. He was a Phantom Thief dammit. If it came down to a Ring Battle he'd easily be able to steal that damned ring from his opposite Cloud. His specialty was item reclamation, and if he couldn't steal half of a damned gaudy ring then he needed to retire. Daisuke had taken up the blade to defend their Sacred Maiden, yes, he had a katana, but he preferred his sakabatō. Daisuke would tarnish his hands with blood if there were truly no other way. Still, the mere fact Daisuke had worked his ass off to learn Spanish, Italian, French, German, Russian, Romanian, Portuguese, Latin, Chinese, and Pashto just meant that they were more than ready to go steal from the Vongola and the CEDEF.

Disclaimer: I do not own Katekyo Hitman Reborn, Black Cat, or D N Angel.


	2. Chapter 2

Chapter 2

Azumano:

Train kicks back and relaxes as Rinslet, Eve, Emiko, and Shizu head off to the spa for a month while Daisuke/Dark go to steal the Vongola Half Rings, and sew mass confusion amongst the Cosa Nostra. Neither one of them needed Mist Flames to disguise themselves, and Daisuke made damned certain he looked innocuous. Like Hell he was keeping his ruby red hair and eyes, those were too identifying. Dark on the other hand, well, he had no problems with gaining new levels of infamy. Sven looks at his Sweeper partner, " You look way too smug, Train. "

Train smirks, " Well, I may be giving the Vongola the run around while Koneko fills out her Guardian positions with appropriate people, though I wasn't expecting Rinslet to be her Storm. She needs Sun and Mist now. "

Sven has to laugh at this, the Vongola thought they were so damned good. They weren't, the Varia were respected, but the Vongola...no chance in Hell. It went downhill ever since Timoteo took over, and appointed Koneko's sperm donor as the External Advisor while also being the Head of the CEDEF. With all three of Timoteo's blood sons iced permanently...well...not being able to protect his heirs reflected poorly on Timoteo. The only reason Koneko was still alive was because of Train, or rather Kuroneko. Koneko was already gaining a name for herself as a junior Sweeper.

The Sweepers left Dark alone once they realized he only stole dangerous artwork that came to life so it could be dealt with appropriately. It wasn't like they'd be able to catch him anyhow, though they did run interference with Krad where applicable. No Phantom Thief sullied their hands with blood, all any of them wanted was to let their reputation live on in infamy. Kosuke would have gone with his son, but his mission was a solo one, and besides, they needed to make sure they had all their defenses ready. Having the Niwas design his home's security system was the best decision he ever made, save for moving to Azumano. His Koneko was thriving, and technically had two boyfriends though they shared a body.

The defenses were only active at night, and there were no traps to wake Koneko up. Anyone whom actually got past the traps then had to deal with Kuroneko himself, and he was very protective of his Glaring dammit. Train still had enough contacts in the dark underbelly of society that were more than willing to send Reborn on the runaround while Koneko found true Guardians. If she got all of her Guardians before Reborn tracked her down then she couldn't get stuck with any that were from civilian backgrounds. Worse would be Mafia Political Match Ups, and his contacts were also letting him know if Nono got it into his head to marry Koneko off, if he did, every candidate would suffer an _accident_. Alright, so maybe Train and Kuroneko were shipping Koneko with Daisuke/Dark.

Italy:

Daisuke smirks deviously, he left the Chiavarone alone because their Decimo suffered enough under Reborn's tender tutoring mercies. Well, he might have stolen evidence that some of his men were actually stealing from Dino, and left little tips on how to handle his paperwork more effectively. Dark is laughing his ass off when Daisuke does this. The Bovino Famiglia, well, a certain Bazooka, and five year old go missing, only to reappear in the Niwa Home thanks to the Sweepers. Niwas were resourceful if nothing else, and Daiki wastes no time in forging the signature of Lambo Bovino's legal guardian, and then has Kosuke become Lambo's new legal guardian. Daisuke could handle a little brother, and Emiko would love to have another child to spoil.

Dark and Daisuke were both very careful to never be seen by the Poison Scorpion, though they did rob her father and his friends blind for how they treated her half-brother Hayato. They also robbed the Carcassa Famiglia blind, after giving notice, freeing Skull, the Cloud Arcobaleno from his contract with them, and sending him to Azumano as well. Odds were good Emiko would fall in love with Oodako, and use Oodako in her training trap courses. They did break into the Varia Headquarters, and moved everything around. Dark was even thoughtful enough to give Luss a new toy as well. The bitching Squalo did when he realized _all of his swords had been moved_ was hilarious.

Instead of moving any of Belphegor's things Dark instead found something else that belonged to the royal family Bel was from, though he did send a missive to Train to _erase_ Bel's brother, permanently this time. Train was all too happy to do that, and then send confirmation of the kill to the Varia Storm as an early birthday present. Belphegor had a mixed reaction to that, on the one hand it meant his twin survived what _he did to him_, but at the same time someone gave him a very thoughtful gift by _permanently removing Rasiel from the Earth_. If Dark just so happens to steal intel on what was really going on in the Vongola from the Miser Mist, and get away with it...well, that had his reputation soaring to new heights.

Gokudera Hayato, when he found out what Dark did to his so called father, he actually hunted the thief down, and thanked him for screwing with his father like that. Dark looks at the bomber, " No problem, kid, no one should be treated the way you were. Now, how would you like a chance to start over, and get away from your sister? "

Hayato straightens, " Reborn wants to bring me in as the Vongola Decima's Storm Guardian. "

Dark cackles, and leads Hayato to his nondescript hotel room, all without anyone following them either. " My Sky already has a primary Storm. See, she wants to get her Guardians before people pressure her to. And she doesn't want them from civilian backgrounds either. I'm her Cloud. Know of any Suns that would like to get out of the area? "

Hayato grins widely, " How is it you actually know where she is? "

" She lives next door to me, and her maternal uncle is Kuroneko. " Dark deadpans.

Hayato's light green eyes bug out at this, " I do know of a Sun Latent, though you'd need to talk to Decimo Chiavarone. She was just discovered to be his niece. "

Dark grins, " I'll work it out somehow. Now, all my Sky needs to do is find a Mist. "

" You'd take me back with you? "

" I'm sending you on ahead. I've picked enough pockets to afford the airfare, I still have things to do here. However, we're disguising you with contacts and a wig. Not to mention making you over as a punk until you get to where I'm sending you. That silver hair is way too recognizable. " Dark says, and starts teaching Hayato the finer points of disguise, diction, body language...it took two weeks, and Dino agreed to send his niece to see if she could Harmonize with the Vongola Decima candidate. Especially after Dark sent more evidence of traitors to his Famiglia straight to him. Dino may not be happy with the Ninth Generation of the Vongola, but helping Decima fill out her Elements before Reborn got to her...he was all for that. Hell, he'd be in the Niwa home to see Reborn get his ass kicked by the house defenses, and Daiki would supply him with a recording, while selling the original to Viper/Mammon/Miser Mist. Skull would also get a copy free of charge as well.

Once Hayato and Merciana are on their way, in such a way that no one caught on Dark and Daisuke get down to the real reason why they were in Italy. To get the damned rings before Iemitsu got their Sky killed due to his _Incompetence_. The Moron was going to be in for a rude awakening when he finally saw his daughter again, that was for sure. Shizu was firmly a Heartnet, and not a Sawada. Stealing both sets of the Half Rings was so damned easy it was pathetic. Hiwatari would be appalled at how easy it was as well. Dear Hermes, were they really that self-confident that they thought no one would have the Balls enough to follow through on stealing from the Vongola. He announced his heists, and made off with both sets of rings, _easily_. He even stole Xanxus out from under them!

He sent Xanxus to Train through the Sweeper channels, and then headed home as himself, after picking up some souvenirs of course. One such being a Sky Flame ring he lifted off of someone undeserving of it. This Sky Ring is A Rank, and more to the point Dark could tell it was designed to _hide Sky Attraction_. He'd hold onto that ring for a little bit, and give it to Shizu on her sixteenth birthday, _as an engagement ring._ He got cookbooks for his mother, fabrics for Risa, a sports catalogue for Riku, E rank Flame Rings for his father, a new Flame resistant whip for Rinslet, a book on Metallurgy for Eve, Italian cigarettes for Sven, several books on Flame Traps for his grandfather, Flame Bullets for Train, and an actual kitten for Shizu.

Azumano:

Dark is literally tackled for his gift of a kitten for his/Daisuke's girlfriend. Xanxus would have laughed, except Train was Quality, as was Dark, and the Trash's biological daughter, though she was Kuroneko's Koneko first and foremost. Train has no problems with helping Xanxus shakes off the rust, and allowing him to recover in peace before he gets back into the game as the Varia Sky. Meeting Shizu, well, Xanxus has no problems with her being Decima, and she had harmonized with Merciana. She'd found an abused little Mist by the name of Nagi, and Train might have iced the girl's mother, mostly so she could get the transplants she needed. He had been a Chronos Number, if he couldn't kill someone and make it look like an _accident_ there was something wrong with him. He figured Saya wouldn't have a problem with that, or the Idiots he killed for going after his niece.

He didn't kill indiscriminately anymore, but since his niece was connected to the Mafia through her _Idiot Sire_, he had to end several _Idiot Mafioso_ for trying to harm her, kidnap her...hell Eve, Sven, and Rinslet had to as well. The traps also ended several an idiot too. Thankfully Sephira had gotten ahold of three children experimented on by their own Famiglia, and taken them into Chronos, mostly so they could get the therapy they needed. Number I in Chronos had ended the Esterneo with extreme prejudice, and filmed what they had been doing for the Vindice. Then again Chronos only went after the Worst of the Worst now that the Apostles were no longer a part of them. Thank God Kuroneko had taken over long enough to kill Creed Diskenth, he was not going to put up with that damned stalker for the rest of his life.

Yes, Train did in fact suffer from Dissociative Identity Disorder, and sadly so did his niece from the two years of extreme bullying she suffered from in Namimori due to that damned seal that did nothing for Sky Attraction. That was where Koneko came into play, both uncle and niece had traumatic childhoods but at least Shizu didn't get turned into an assassin. Well, she'd make a damned good one, but she was a Sweeper, not an Eraser. However since she was the only one on the records left to take over the Vongola that was eligible...she'd end up killing more than her fair share once Reborn was actually allowed to find her. If Xanxus ordered Mammon to train Nagi up on how to use Mist Flames, no one said anything.

Hayato and Lambo had been adopted fully into the Niwa family, Lambo having an actual mother figure around was actually a rather well behaved little boy for the most part. The Niwas put their family connections to work to train Shizu's elements up. Dark and Daisuke were already Quality, Rinslet was a tricky bitch that was training with the same Oyabun that was giving Shizu the lessons she needed to know how to run a Crime Family. Rinslet would be a tough fight for the Prince, except Xanxus was alright with Shizu, her uncle was Quality, even if he found out about his older half-sister conceived through violence too late to save his litter mate, but he had been in time to save the kitten. Mammon was so looking forward to being allowed to sell the upcoming blackmail on Reborn. It made sense to let Dino and Skull have it for free...they suffered the worst at Reborn's hands.

That Mammon would have to pay for the original was of little consequence. People would pay _any price for viable blackmail on Reborn_. He was damned good at what he did, but he was also _an ass of the highest order_. Loki at his worst was more tolerable than Reborn at times. Xanxus was so enjoying his time in Azumano, training with _Kuroneko himself_ was eye opening, and the man only killed in defense of his niece, getting rid of the Trash that tried to harm her, or use her against the Vongola as a whole. The rest of the time he was a Sweeper, sure there were a few Trash that the world was better off without...but for the most part Train Heartnet did not kill anymore in memory of the only female so far to catch his interest, that she'd been cut down the way she had been was a tragedy.

Any female that had that much of an impact on someone like _Kuroneko_ had to be Quality, and one helluva woman. Merciana had actually been taught how to control her Flames by her uncle since Dino did happen to be a Sunny Sky, and Dino's Sun had given her some needed lessons as well. Merciana had decided to be a Poison Specialist, one whom coated any weapon she used with them. Gaining immunities to said poisons was going to be a bitch and a half though.

Disclaimer: I do not own Katekyo Hitman Reborn, Black Cat, or D N Angel.


End file.
